loose primer pocket

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Mark_Mark

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How do you know if a primer pocket is too loose. And what would happen if you fire a cartridge with a loose primer
 
If it held together long enough to be fired...then it worked as intended ;)

For gas guns, it is possible for residual gas pressure to push the primer out during extraction and cause a jam.

I think it's an experience thing...there are some that is loose enough that once you seat the primer, and then take the cartridge and tap the rim on a wooden surface...if it falls out, it's no good. I usually can feel the primer seating force. If it felt it went in too easily, I will do the tapping test. It is marked for last use even if it does not fall out.
 
If it held together long enough to be fired...then it worked as intended ;)

For gas guns, it is possible for residual gas pressure to push the primer out during extraction and cause a jam.

I think it's an experience thing...there are some that is loose enough that once you seat the primer, and then take the cartridge and tap the rim on a wooden surface...if it falls out, it's no good. I usually can feel the primer seating force. If it felt it went in too easily, I will do the tapping test. It is marked for last use even if it does not fall out.
I was thinking about tapping it on wood and see if it falls out. Didn’t know the physics behind primer pockets
 
This is one of the reasons that I hand prime. I go mostly by feel. If I seat a primer that just feels to easy I'll put that case to the side and later on deprime it and recover the primer.

There are a few companies that offed a go-no go gauge for test primer pockets. I just go by feel.

As others have said, a loose primer can etch your bolt face with hot gas, cause a jam and possibly break something in the trigger.
 
How do you know if a primer pocket is too loose.
By feel when seating. I've tried a gauge and find it less useful than feeling seating.

And what would happen if you fire a cartridge with a loose primer
In rifles: the first symptom is a gas leak around the primer than etches the bolt face. This is Not Good.

In pistols: gas leaking is possible, but I've never seen it, or a breach face etched by it.
 
If the primers seat with very little effort either in a hand primer or on a press, then you're getting close to the end of the run for that lot of brass. For instance, I've run some 9mm out to 8x, and there just is no "crispness" when the primer seats. No cracks in the neck or sizing problems, etc, just loose pockets.

My practice is to toss the bunch at that point. I do put up with some looseness as I load some light 9mm rounds for my granddaughter, but the cases are gone after that.

I've never seen a primer leak and don't want to.
 
all this is freaking me out. I primed about 400 cases. I’m going to decap them and start over. Toss out the loose primer pocket case
 
all this is freaking me out. I primed about 400 cases. I’m going to decap them and start over. Toss out the loose primer pocket case

I wouldn’t go that far.:)

If they haven’t fallen out yet, tap them. I’d just use them. I know I wouldn’t reprime them if I did take them down. Brass is cheap.
 
If they stayed in during routine handling, they are probably good for one more firing. Then check the effort needed to seat a new primer when reloading and decap and discard any "loose" feeling pockets...

I have only found loose pockets on some upper loaded 308 brass, and that was after several reloadings. Normally other things happen before loose pockets; split necks/bodies, damaged heads, case separation, etc...
 
Are we talking high pressure rounds or moderate pressure rounds?

Tap the base of each cartridge and then feel and see if any primers have protruded. If not, I would go forward with loading and firing the cartridges. In the future I would set aside anyone that feels loose in a separate bin to evaluate later.

Just something to ease your worries. Think about all those who load on a progressive press and miss loose primers (as one cannot feel them like a hand primer), myself included.
 
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of 400, 5-8 slipped in real easily. No worries???

Boy that'd be a hard call. If they were 45auto, 38spec or even 9mm I'd prob shoot em and then toss the cases. Tossing 400 cases with a 2% failure rate might not go over too easy right now with brass being a bit more scarce. If it were 223 I'd prob go back through and separate the loose ones out (as much of a PITA as that sounds) as I really hate etched bolt faces.
 
I hand prime. When I feel one that goes in too easily I take something that I can use to push the primer out with (lately it is the decap rod from my Lee Loader) and try to push it out. If it comes out, into the scrap bucket. If it stays a sharpie mark on the headstamp area will mark it to be scrapped next time I try to deprime them.
 
I hand prime. When I feel one that goes in too easily I take something that I can use to push the primer out with (lately it is the decap rod from my Lee Loader) and try to push it out. If it comes out, into the scrap bucket. If it stays a sharpie mark on the headstamp area will mark it to be scrapped next time I try to deprime them.

Good system that makes logical sense.
 
For a punch it just has to go through the primer pocket enough to be able to push the primer out. About 1/16 inch past the case head. I have used a Lee universal deprimer held in my hand, a spare Lee pistol deprimer rod, and an old section of car antenna that I ground down to fit the primer pocket as well as the decapping rod in one of my Lee loaders.
If the primer is loose the biggest problem would be falling out and stopplng the firearm from functioning.
 
I use pin gages to check primer pockets. The pin gage size corresponds to SAAMI max diameter, -0.0002”. If it enters the pocket I’ll scrap the case. If it doesn’t it’s good for another reloading. Here’s the larger primer example (SAAMI max is 0.210 and the minus sign means it is ground to be 0.0002” under that). On the left is bad, on the right is good

index.php
 
Not enough info for me to make a call. Semi auto Rifle? Heavy revolver loads? Depending on response I might shoot whatever gun they go in as a single shot.

But more than likely I’d:

Drop them on a wooden cutting board or like surface a couple of times as mentioned previously.

Then use something like Markron Primer sealer for a little extra retention and be cognizant of this issue and cull the lose ones next time.

Lesson learned hopefully. I had this issue with Fed Brass in .327 FM on the 1st reload. Tossed 300-400 plus and will toss all the Fed brass once all are shot and stay with Starline exclusively for this caliber.
 
If one feels like it's too loose, I take a small punch and see if I can push it out by hand. With that said, different mfg have a slightly different size. Changing primer mfg may gain you a few more reloads.

Example: Rem 7 1/2 are smaller than CCI #41 and Fed 205MAR. So all I have to do is switch mfg and your good to go. I normally mark the brass with a marker around the base to tell me it's requires a larger primer.
 
I've gotten to the point that I use a gauge on all my rifle brass right after cleaning and before I do any more prep work:

https://ballistictools.com/store/small-and-large-primer-pocket-gauges

2-swage-gauges-228x228.png

At $20 it's cheap insurance and has saved me way more than $20 in time prepping brass that was shot out. For the rounds that the OP mentioned, I'd tap the rim on a wooden block and discard (pull the bullets) on any rounds that displayed set-back. Then discard that brass, although often pricey, brass is still a consumable.
 
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